Steps to reproduce the issue

Use Joomla subform on PHP older than 5.5

Expected result

Works as expected

Actual result

Fatal error: Can't use function return value in write context in /home/content/76/10380776/html/imbarcoimmediato/layouts/joomla/form/field/subform/repeatable-table.php on line 59

System information (as much as possible)

Joomla 3.9.3, PHP 5.4.19 (it's a client website)

Additional comments

The line of code causing the error is here https://github.com/joomla/joomla-cms/blob/staging/layouts/joomla/form/field/subform/repeatable-table.php#L59 . According to php manual http://php.net/manual/en/function.empty.php:

Prior to PHP 5.5, empty() only supports variables; anything else will result in a parse error

Maybe we can change if (!empty(JText::($field->description))) to if (JText::($field->description) !== '') or add a new variable to store JText::_($field->description) before passing it to empty call